Liquid level alarm system



April 29, 1958 s. STINER ET AL LIQUID LEVEL ALARM SYSTEM Original Filed April 16, 1952 STEWART STINER CHARLES E STEPHENSON ALLEYNE C. HOWELL JR.

IN V ENTORS 1 ATTORNEYS United States Patent i LIQUID LEVEL ALARM SYSTEM Stewart Stiner, Riverdale, and Charles F. Stephenson, New York, N. Y., and Alleyne C. Howell, In, San Francisco, Calif., assignors, by mesne assignments, to Color Carousel Corp., Staten Island, N. Y., a corpora tion of California Original application April 16, 1952, Serial No. 282,652,

new Patent No. 2,787,402, dated April 2, 1957. Divided and this application August 9, 1956, Serial No. 605,913

3 Claims. (Cl. 200-84) The present invention relates to a liquid level alarm system suitable for use in connection with a plurality of liquid storage tanks disposed in a substantially circular arrangement and carried by revoluble supporting means.

Thesystem includes a float disposed in each tank and responsive to the liquid level therein. There is an actuating member for each tank the position of which is controlled by the float. All of the actuating members travel in a common circular path. There is a stationary alarm initiating device located in proximity to the circular path and which will be actuated in response to the assumption by any actuating member of a position corresponding to a low liquid level, for example, this indicating that the level in one of the storage tanks is low and that the supply of liquid requires replenishing.

This application is a division of our copending application, Ser. No. 282,652, filed on April 16, 1952, now Patent No. 2,787,402, issued April 2, 1957.

The liquid level alarm is illustratively shown in connection with a paint mixing machine of the type described in said Patent No. 2,787,402.

Various objects, features and advantages of the invention will become apparent upon reading the following specification together with the accompanying drawing forming a part hereof.

In the drawing, the single figure is a perspective view looking in an upward direction and showing a paint mixing machine in which the liquid level alarm system of the present invention is included.

The paint mixing machine is described in detail in Patent No. 2,787,402 and will therefore be described only briefly in connection with the present liquid level alarm system.

The paint mixing machine comprises a plurality of liquid storage tanks or reservoirs 20 shown individually secured at their inner upper edges to an upper supporting ring 21 by screws 22 which engage threaded collars 23 carried by the tanks 20. The tanks 20 are disposed in a generally circular arrangement and have flat converging sides. The tanks 20 are convexly rounded at their outer end surfaces to form a smooth cylindrical periphery when mounted together as shown in Fig. 1. Their inner end surfaces are concavely rounded to conform to the curvature of supporting ring 21, and to bear against an upper plate 24 of the same diameter as supporting ring 21.

Rigidly secured to upper plate 24, are a plurality of positive displacement pumps, shown by way of illustration as gear pumps 25, an individual pump being provided for each storage tank. No specific type of positive displacement pump is shown since any type of pump is suitable for use with the present invention provided that it may be driven by a revolving shaft and that the volume of liquid pumped corresponds accurately to the number of revolutions of the driving shaft. A gear pump has been selected by way of illustration, since its char- 2,332,865 Patented Apr. 29, 1958 acteristics meet these requirements, but its internal details have not been shown since they may be conventional in all respects.

Each gear pump 25 is supported from a supporting collar 26 secured to the under side of upper plate 24, the supporting collar including suitable bearings for the pump drive shaft 27.

Disposed on the upper side of upper plate 24 and fixedly secured to each pump drive shaft 27 is an individual pump drive gear 28, all of which mesh with a common main pump drive gear (not visible in the drawing) which is fixed to the upper end of a main pump drive shaft later to be described.

Each of the gear pumps 25 is provided with an inlet connection 30 from the bottom portion of its associated storage tank 20 and an outlet connection 31 which extends to a three-Way valve 32. From valve 32 a further duct or connection 33 extends into the tank 20 to a point near its upper end, where it terminates in an outlet 34.

As shown in the drawing, the return duct 33 terminates in an outlet 34 which is located above the highest liquid level in each tank. In the embodiment illustrated, it is contemplated that the rate of flow of the recirculating liquid is sufiiciently slow so that it will slowly ooze out of the cut-off end of duct 33 which forms the outlet 34, the outer surface of duct 33 acting as a surface for smoothly flowing the returning liquid back into the liquid in the tank without entraining air.

With the valve 32 in its normal position, liquid is drawn from the bottom of the tank 20 through the pipe 30 into the inlet side of gear pump 25. Gear pump 25 forces the liquid into the pump outlet connection 31 and through valve 32 into pipe 33 and outlet 34 from which the liquid drops back into the main supply contained in the storage tank 20. So long as gear pumps 25 are in operation, the liquid stored in each tank 20 is recirculated, thereby preventing the settling of any solids or the accumulation thereof at the bottom of any of the tanks 20.

The upper plate 24 is secured to a supporting flange 35 by bolts 36 and the upper plate 24 and flange 35 are carried by a hollow vertical drive shaft 37. Because hollow shaft 37 carries the entire weight of all of the storage tanks 20 together with their associated gear pumps 25 and valves 32, suitable thrust bearings must be provided, together with bearings to prevent lateral movement of the hollow shaft 32. These are not specifically shown, but may be of any desired type and may be located in any desired positions in known manner.

Disposed within hollow shaft 37 is a pump drive shaft 38 which is fixedly connected to the main pump drive gear, as described above, at its upper end and at its lower end to a counting cam assembly designated generally as 39, which comprises a sheave connected by a V-belt 42 to a further sheave 43 which is driven by a pump drive motor 44 through a speed reducing mechanism 45. Assuming hollow shaft 37 to be stationary, motor 44 will drive all of the pumps 25 through main pump gear and pump drive shaft 38, since all of the individual pump gears 28 mesh with the main pump drive gear.

The hollow shaft 37, at its lower end, carries a pcripherally grooved selector wheel 46 which is driven through a speed reducing pulley 47 by a motor 48, the driving connection to the motor 48 comprising a speed reducing mechanism 49 and two V-belts 50 and 51, the V-belt 50 extending from motor speed reducer 49 to pulley 47 and belt 51 from pulley 47 to the periphery of the selector wheel 46.

Motor 43 thus drives hollow shaft 37, carrying with it all of the tanks 20, valves 32 and pumps 25. With pump drive shaft 38 stationary, all of the individual pump drive gears 28 will pass around the stationary main pump drive gear in mesh therewith and will thus simultaneously operate their respective pumps 25 at a reduced speed suitable for recirculation of the liquids in the several storage tanks 20. By the addition to the group of tanks 20 of suitable coloring, lettering, or the addition of indicia, this slow speed rotation of the group of tanks 20 may be utilized for a sales promotional display eflect accompanying the slow rotary movement of the group of tanks.

Disposed on the under side of selector wheel 36 are a plurality of stop studs 52. A floating stop arm 53, pro vided with a longitudinal slot through which hollow shaft 37 passes freely, and is slidably retained positioned between an upper collar 55 and a lower collar 56, thus being freely radially movable inwardly and outwardly with respect to selector wheel 46 within the limits of travel imposed by the length of the slot -41. On its upper surface, floating arm 53 carries a stop-dog not visible in the drawing which is selectively engageable with any one of the stop studs 52 when the arm 53 is in its radially outward position. In the inward position of arm 53 the stop studs 52 pass freely by the stop-dog 57.

Arm 53 is urged radially inwardly toward shaft 37 by a tension spring 58, one end of which is secured to a fixed bracket 59, the opposite end being secured to arm 53 at a hole 60 therein. A solenoid designated generally as 61 and-comprising an operating winding 62 and a plunger 63 is shown provided with a link member 64 which extends to the floating arm 53. Upon energization of operating winding 62, the plunger 63 is drawn inwardly within the solenoid 61 and link 64 thereupon draws the floating arm 63 outwardly into a position where the dog 57 is placed in the path of travel of the studs 52. One of these studs will thereupon engage the dog 7 and will force arm 53 to rotate along with the selector wheel 46. This action is retarded and damped by suitable mechanism illustratively shown as an air check 65, the air check 65 being arranged for quick return action in the usual manner.

Upon being drawn outwardly by solenoid 61, the floating arm 53 will travel along with the particular stud 52 engaged by dog 57 until it reaches its limit of travel at which point two switches 66 and 67 are actuated, the purpose of this actuation being more fully set forth in Patent No. 2,787,402.

When energized, motor 48 drives the selector wheel 46 and thereby rotates hollow shaft 37 and the several storage tanks 24) together with the assembly of gear pumps 25. Since the individual pump driving gears 23 i are being rotated with respect to the main pump driving gear, referred to above, which is stationary during slow rotation of the tanks and with which the individual gears 28 are in mesh, all of the gear pumps are caused to be rotated about their axes at relatively low speed, thereby each circulating and recirculating the liquid in its associated storage tank 20. Apart from this action, the remainder of the device is not activated.

A group of switches 90, one of which corresponds to each of the storage tanks 20, is arranged in conjunction with a selecting mechanism (not shown) to control the motor 48 and arm 53 to bring any desired one of the tanks 20 into dispensing position with respect to a container 103. There is also, a group. of. cam actuated switches 109, and 111 which cooperate with counting apparatus (not shown) to measure the amount of liquid dispensed from any tank 20 into the container 163. The counting apparatus controls the operation of a valve actuating solenoid 127.

The valve actuating solenoid 127 is fixedly secured to the upper end of a supporting column comprising a hollow cylindrical member 131 and four stay bolts 132 which clamp the supporting column against a base plate 1.33, the cylindrical member 131 being held between upper and lower column end plates 134, the valve actuating solenoid 127 being mounted on the upper column end plate 134 in operative relationship to any valve 32 in dispensing position.

in order to direct attention to the fact that the liquid level in one or more of the containers is low, and that refilling is required, each container 20 is provided with a ball float 161 (Fig. 1) carried by an arm 162, the arm 162 being movably secured to a fixed pivot at 163 and having an extending portion 164 whose end is shown in proximity to the upper supporting ring 21. When the liquid level drops sufficiently low, arm 162 pivots about 163 and the extending portion 164 rises. A stationary switch mechanism 165 is fixedly positioned directly above the path of travel of the extending portions 164, and its actuating lever 166 will be engaged by any of the extending arm portions 164 which has risen to a sufiicient extent as a result of the lowering of the liquid level in its associated tank. The contacts of switch 165 may be connected to an alarm circuit of any desired type which may comprise an audible signal or a visual signal, or both, together with facilities for silencing the audible signal, if desired.

We have shown what we believe to be the best embodiments of our invention. We do not Wish, however, to be confined to the embodiments shown, but what we desire to secure by Letters Patent is the invention as defined in the appended claims.

We claim:

1. In a liquid level alarm system for a device comprising a plurality of liquid storage tanks disposed in a substantially circular arrangement, said tanks being supported by common revolving supporting means: float means disposed in each tank and responsive to the level of the liquid therein; an actuating member for each tank the position of which is controlled by the float means, all of said actuating members traveling in a common circular path; and stationary alarm initiating means disposed in proximity to said path and responsive to any actuating member which assumes a predetermined position in response to a condition of liquid level in its associated tank.

2. An alarm system according to claim 1, wherein said float means comprises an arm, and a float disposed at and fixed to one end of said arm, the other end of said arm being connected to pivot means which is fixed with respect to said common supporting means.

3. An alarm system according to claim 2, wherein said actuating member is formed by an extending portion of said arm, said extending portion being displaced in accordance with movements of the float which is disposed at said one end of said arm.

No references cited. 

